-x cpp-output not working

When using ccache and compilng files with the -x c option, ccache first generates the preprocessed file then runs the intel compiler with -x cpp-output. According to the docs, it should treat the preprocessed file as a C file (not C++), but I'm getting void * casting errors. I don't see the same error with gcc, this looks like a bug?

I'm using Intel 13.1.1 20130313 on Fedora 14 64 bit.

Thanks